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role in angiosperms

Very different plant forms result from simply changing the lengths of the
internodes. Extreme shortening of the
internodes results in rosette plants, such as lettuce,
Lactuca sativa (Asteraceae), in which the leaves develop but the
internodes between them do not elongate. Extreme lengthening of the
internodes often results in twining vines, as in the yam,
Dioscorea esculenta...

The stem has growth periods similar to those of the root, but longitudinal regions are not as obvious as in the root until the nodes become differentiated and
internode lengths increase. Elongation of
internodes involves many cell divisions and is followed by cell elongation. At this point, growth in thickness involves some radial cell division and cell enlargement.

structure in plants

...of this bud and its adjacent tissues, the stem increases in height. Lateral buds and leaves grow out of the stem at intervals called nodes; the intervals on the stem between the nodes are called
internodes. The number of leaves that appear at a node depends on the species of plant; one leaf per node is common, but two or or more leaves may grow at the nodes of some species. When a leaf drops...

tree stems

The stem is divided into nodes (points where leaves are or were attached) and
internodes (the length of the stem between nodes). The leaves and stem together are called the shoot. Shoots can be separated into long shoots and short shoots on the basis of the distance between buds (
internode length). The stem provides support, water and food conduction, and storage.